A. Technical Field
The disclosure generally relates to mobile communications. More particularly, the disclosure relates to managing various mobile communication protocols in a unified manner.
B. Related Art
In recent years, the demand for mobile communications has steadily increased. With the increase in demand, the mobile communications industry has incorporated a variety of different protocols. Accordingly, a system for interworking the various accepted protocols is needed.
Varieties of mobile communication protocols are available including cellular, mobile IP, DHCP/DNS and SIP. While the protocols vary in how they function, each implementation of the protocol needs to support standard functions including location registration, location resolution, authentication, authorization, and accounting. Location registration relates to a mobile terminal announcing and receiving confirmation of its location within a network or platform. Location resolution relates to the determination of where a mobile terminal is in a network. Authentication relates to a function of a network determining whether a certain mobile user is a confirmed user of a network through interactions with at least one database. Authorization relates to a function of a network determining whether a certain mobile user is allowed to use a service of the network through interactions with at least one database. Accounting relates to a function of a network monitoring and assessing fees to a certain mobile terminal. Authentication, authorization, and accounting are referred to generally as xe2x80x9cAAAxe2x80x9d functions. In general, location registration occurs at the power-on phase of a terminal and during the handoff of a terminal between sites in a network. At the same time, authentication may be performed. Location resolution generally occurs when a first terminal attempts to set up a communication channel with a second terminal. Again, authorization may be performed at this time for both the first terminal and the second terminal. Accounting is generally performed while a terminal is actively communicating with another terminal. For simplicity, the terminal initiating a communication is herein referred to as the xe2x80x9ccallerxe2x80x9d and the terminal attempting to be contacted is the xe2x80x9ccallee.xe2x80x9d
For purposes herein, a platform may be defined as a portion of a network where identical signaling protocols handle the operations of connection set-up, connection tear-down, hand-off, location registration, location resolution, and accounting (or charging). Moreover, a platform may be a portion of a network that is provided by one operator, even if the signaling protocol for Operator A""s network is the same as the protocol as Operator B""s network. For example, one operator (for example, Bell Atlantic Mobile) may have a number of platforms within the network controlled by the operator. The first platform would use CDMA, the second would use Analog AMPS, and the third would use Mobile IP, etc. In the latter case, the border between platforms using identical protocols but operated by different operators is controlled by a mobility database. Each operator manages its mobility database independently.
A number of the above-described functions are performed in databases connected to the network servicing the terminals. FIG. 1 shows a conventional arrangement for mobile communication networks as including databases. The databases store various information for terminals including the terminals"" terminal identification (TID), the terminals"" location identification (LID), passwords, permission lists, and accounting information. It is noted that some platforms do not support the concept of a mobility database and a common LID format.
As shown in FIG. 1, each network has a mobility database as including the TID, LID, and other information for each terminal serviced by it. For example, cellular network 101 (for instance a 1G/2G cellular network) includes mobility database 105 called a HLR (Home Location Register), which stores an E.164 number as the TID, platform-specific information as LID, a set of platform-specific information as the password permission list and accounting list. The VLR (Visitor Location Register), which stores a copy of the information stored in the HLR, may be used in the well-known cellular network system in order to reduce traffic regarding location registration and accounting.
Mobile IP network 102 includes mobility database 106 called HA (Home Agent), which stores IP address as TID and LID, a set of platform-specific information as password, permission list and accounting list. The current standard of Mobile IP (RFC2002) includes a special function called FA (Foreign Agent), which handles Mobile IP-specific functionalities. However, these Mobile IP-specific functionalities are well-known and are beyond the scope of the invention. DHCP/DNS network 103 includes mobility database 107 called Domain Name System, which stores Host Name and Domain Name as TID, IP address as LID, and a set of platform-specific information as password, permission list and accounting list. Here, DHCP (Dynamic Host Configuration Protocol) may be used for assigning an IP address at an access point where a Mobile Terminal currently visits. Also, the dynamic DNS currently discussed at IETF may be used for advertising the assigned IP address to the whole network. SIP network 104 includes mobility database 108 called SIP Proxy, which stores SIP URL as TID and LID, and a set of platform-specific information as password, permission list and accounting list.
An end user desires the ability to communicate with anyone, irrespective of the network in which the called party (or callee) is located. Because each of these networks has different protocols, no direct connection is possible. Further, higher order functions (including authentication, authorization, and accounting) of a terminal on a foreign network are not possible as no interchange of information between the mobility databases 105-108 exists.
A system has been proposed that attempts to coordinate IP and non-IP communications. A white paper by Cisco Systems describes Cisco""s architecture for voice/video/data integration on the Internet. The paper relates to providing a method of internetworking among plural mobile platforms including IP-based platforms. Specifically, the paper defines a four layer architecture including a clients level 112, an infrastructure level 111, a call processing level 110, and an application level 109 as shown in FIG. 1B. The application level 109, which is open to development by other entities, is provided to realize sophisticated services like Unified Messaging. The call processing level 110 functions as a call manager in that it controls voice calls on the Internet. The call manager provides the traditional phone""s xe2x80x9clook and feelxe2x80x9d to IP-based voice applications. Also, if required, the call manager handles the internetworking between IP and PSTN communications as shown in FIG. 1C. FIG. 1C includes an P-based network 114 (including routers and the like) and a PSTN network 115. An example of the initiation of a call is provided. IP-based terminal 119 provides a request to call manager 116 to place a call. The call manager 116 exchanges control information with the call setup portion 117 for the PSTN network 115 servicing PSTN terminal 118. Once all information has been exchanged, a call is established between IP-based terminal 119 and PSTN terminal 118 through physical link gateway 113. The call manager 116 controls the physical link gateway 113 to set up the desired call. While disclosing a method for interworking IP telephony and PSTN, the above-described system fails to disclose mobility-related functions.
Another approach has been suggested by TIA (the Telecommunications Industry Association). TIA supports the TR45.6 architecture for implementing IP service. This architecture has two tiers including an access network and a core network. Referring to FIG. 1D, the core network is represented by the mobile IP-capable IP network 120. The access networks are represented by the cellular networks 123 and 124. IP network 120 includes foreign agent FA 121 and home agent HA 122 that functions as the mobility database (monitor and coordinate location registration and resolution) for this network. Each of networks 123 and 124 includes visiting location registers VLR 126 and 129 and home location registers HLR 127 and 130. The combination of the HLRs and the VLRs functions as the mobility database for these networks. It is noted that the IP network 120 is not necessarily synonymous with the Internet. The Internet is open to all traffic. IP network 120 may be part of the Internet or may be separate from the Internet. Similarly, the IP network 120 may be limited to IP communications.
Referring to FIG. 1D, if one wanted to communicate with a mobile terminal whose home network was a different cellular network than what the mobile terminal was on, then one would use the IP network 120 to transfer calls. This means the mobile terminal should be IP compatible if one wanted to communicate with other terminals on other platforms. This creates in each mobile terminal the requirement that all terminals must be IP-compatible. This limits the effectiveness of non IP-compatible mobile terminals.
Accordingly, an object of the present invention is to provide a system and method for internetworking among plural mobile platforms.
It is another object of the invention to provide a system and method for internetworking among plural mobile platforms including the IP-based platform.
It is yet another object of the present invention to provide a system and method to realize communication between mobile terminals of different platforms.
It is a further object of the present invention to provide a system and method to realize communication between non-IP-capable mobile terminals and IP-capable mobile terminals.
These and other objects of the invention will become apparent through implementing the system described herein.
The present invention relates to a unified mobility management system and method for enabling handling of communications in a unified manner. Using a unified mobility manager, a terminal may register its location with its home database in a foreign network. In addition, the terminal may be found through interactions with its home database. Further, authentication, authorization, and accounting may be performed for a terminal outside its home network through accessing its home database.
Signaling messages from a mobile terminal connected to operator A""s network are routed to the mobility database operated by operator A first. If necessary, a mobility management gateway intercepts the signaling messages and redirects the messages to another mobility management database operated by the native operator of the mobile terminal.
The unified mobility manager (referred to herein as a xe2x80x9cUMMxe2x80x9d) includes the ability to translate addresses from one protocol to another protocol across platforms. The UMM intercepts information directed for another platform and passes the received information to the desired network.